Synoviolin is a protein which was discovered as a membrane protein that is over-expressed in synovial cells obtained from rheumatoid arthritis patients (Patent Document 1). Synoviolin has been determined to be a molecule that is essential for the onset of rheumatoid arthritis according to research conducted using genetically modified animals.
Synoviolin has been suggested to have a RING finger motif based on analyses using a protein structure prediction system. This motif is found in large numbers in an enzyme known as E3 ubiquitin ligase, which plays an important role in protein ubiquitination. In actuality, synoviolin has been demonstrated to have self-ubiquitination activity, which is a characteristic of E3 ubiquitin ligase (Patent Document 1). However, many of the functions of synoviolin in vivo remain unknown. More specifically, there have been no reports regarding whether the disruption of synoviolin gene causes weight loss.
Obesity is caused by such factors as lack of exercise, habitual overeating or metabolic disorders attributable to genetic factors or endocrine diseases. Obesity is a risk factor that can induce various adult-onset diseases such as myocardial infarction or arteriosclerosis, and since it also contributes to exacerbation of these diseases, early treatment and prevention are extremely important. Although treatment involving hormone drugs or metabolism promoting agents has conventionally been used in pharmacotherapy for obesity, hardly any drugs are known that are able to reduce weight safely or inhibit weight gain.